I've noticed in v1.7.0 that when I write an internal note I get a notification e-mail - which I thought was a little redundant. Investigating the contents of the Ticket class, it seems that this is not intended behaviour, so I went ahead and made the following, one-line change (patch from TLD of osTicket installation; line numbers may, and probably will, vary):
--- include/class.ticket.php 2013-04-01 23.000000000 -0600
+++ include/class.ticket.php 2013-05-30 13.000000000 -0600
@@ -1550,7 +1638,7 @@
$sentlist=array();
foreach( $recipients as $k=>$staff) {
if(!$staff || !is_object($staff) || !$staff->getEmail() || !$staff->isAvailable()) continue;
- if(in_array($staff->getEmail(), $sentlist) || ($staffId && $staffId==$staff->getId())) continue;
+ if(in_array($staff->getEmail(), $sentlist) || ($vars && $vars==$staff->getId())) continue;
$alert = str_replace('%{recipient}', $staff->getFirstName(), $msg);
$email->sendAlert($staff->getEmail(), $msg, $alert, $attachments);
$sentlist = $staff->getEmail();